#40: properly concatenating expression/token sequences in uri interpolator

2 files changed, 46 insertions, 6 deletions

diff --git a/core/src/main/scala/com/softwaremill/sttp/UriInterpolator.scala b/core/src/main/scala/com/softwaremill/sttp/UriInterpolator.scala
index f1e6beb..fe19358 100644
--- a/core/src/main/scala/com/softwaremill/sttp/UriInterpolator.scala
+++ b/core/src/main/scala/com/softwaremill/sttp/UriInterpolator.scala
@@ -437,11 +437,46 @@ object UriInterpolator {
       case x       => Some(x.toString)
     }
 
-    private def tokensToStringSeq(t: Vector[Token]): Seq[String] = t.flatMap {
-      case ExpressionToken(s: Seq[_]) => s.flatMap(anyToStringOpt).toVector
-      case ExpressionToken(e)         => anyToStringOpt(e).toVector
-      case StringToken(s)             => Vector(decode(s))
-      case _                          => Vector.empty
+    private def tokensToStringSeq(tokens: Vector[Token]): Seq[String] = {
+      /*
+      #40: when converting tokens to a string sequence, we have to look at
+      groups of string/expression (value) tokens separated by others. If there
+      are multiple tokens in each such group, their string representations
+      should be concatenated (corresponds to e.g. $x$y). A single
+      collection-valued token should be expanded.
+       */
+
+      def isValueToken(t: Token) = t match {
+        case ExpressionToken(_) => true
+        case StringToken(_)     => true
+        case _                  => false
+      }
+
+      @tailrec
+      def doToSeq(ts: Vector[Token], acc: Vector[String]): Seq[String] = {
+        val tsWithValuesPrefix = ts.dropWhile(to => !isValueToken(to))
+        val (valueTs, tailTs) = tsWithValuesPrefix.span(isValueToken)
+
+        valueTs match {
+          case Vector() => acc // tailTs must be empty then as well
+          case Vector(ExpressionToken(s: Seq[_])) =>
+            doToSeq(tailTs, acc ++ s.flatMap(anyToStringOpt).toVector)
+          case _ =>
+            val values = valueTs
+              .flatMap {
+                case ExpressionToken(e) => anyToStringOpt(e)
+                case StringToken(s)     => Some(decode(s))
+                case _                  => None
+              }
+
+            val strToAdd =
+              if (values.isEmpty) None else Some(values.mkString(""))
+
+            doToSeq(tailTs, acc ++ strToAdd)
+        }
+      }
+
+      doToSeq(tokens, Vector.empty)
     }
 
     private def tokensToStringOpt(t: Vector[Token]): Option[String] = t match {
diff --git a/core/src/test/scala/com/softwaremill/sttp/UriInterpolatorTests.scala b/core/src/test/scala/com/softwaremill/sttp/UriInterpolatorTests.scala
index 9fc2d3a..acfa9d4 100644
--- a/core/src/test/scala/com/softwaremill/sttp/UriInterpolatorTests.scala
+++ b/core/src/test/scala/com/softwaremill/sttp/UriInterpolatorTests.scala
@@ -41,6 +41,9 @@ class UriInterpolatorTests extends FunSuite with Matchers {
     "authority" -> List(
       (uri"http://$v1.com", s"http://$v1.com"),
       (uri"http://$v2.com", s"http://$v2encoded.com"),
+      (uri"http://$v1.$v2.com", s"http://$v1.$v2encoded.com"),
+      (uri"http://$v1$v2.com", s"http://$v1$v2encoded.com"),
+      (uri"http://z$v1.com", s"http://z$v1.com"),
       (uri"http://$None.example.com", s"http://example.com"),
       (uri"http://$None.$None.example.com", s"http://example.com"),
       (uri"http://${Some("sub")}.example.com", s"http://sub.example.com"),
@@ -78,7 +81,9 @@ class UriInterpolatorTests extends FunSuite with Matchers {
       (uri"http://example.com?x=$v1", s"http://example.com?x=$v1"),
       (uri"http://example.com/?x=$v1", s"http://example.com/?x=$v1"),
       (uri"http://example.com?x=$v2", s"http://example.com?x=$v2queryEncoded"),
-      (uri"http://example.com?x=$v3", s"http://example.com?x=$v3encoded")
+      (uri"http://example.com?x=$v3", s"http://example.com?x=$v3encoded"),
+      (uri"http://example.com?x=$v1$v1", s"http://example.com?x=$v1$v1"),
+      (uri"http://example.com?x=z$v1", s"http://example.com?x=z$v1")
     ),
     "query parameter without value" -> List(
       (uri"http://example.com?$v1", s"http://example.com?$v1"),